Nature Materials, Published online: 30 June 2026; doi:10.1038/s41563-026-02647-xConductivity and superconductivity at the LaAlO3/SrTiO3 interface are well established. Now, in a layer-by-layer fashion, oxygen octahedra rotations, polar displacements and vibrational modes that are parallel and perpendicular to the interface are probed. A doping-dependent study reveals phonon modes related to oxygen vibrations, and their connection to superconductivity is discussed.